Ryukyu fruit bat
| Ryukyu fruit bat | ||||||||||||
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Ryukyu fruit bat |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Pteropus dasymallus | ||||||||||||
| Temminck , 1825 |
The Ryukyu flying fox or Formosan flying fox ( Pteropus dasymallus ) is a kind from the family of bats . It is common in Japan on the eponymous Ryūkyū Islands as well as on some islands off the coast of Taiwan and in the north of the Philippines . The species is classified as endangered, and individual subspecies are also threatened with extinction.
Characteristics and way of life
The Ryukyu fruit bats have a wingspan of up to one meter. Unlike other bats , fruit bats do not have echolocation , but they have good eyesight and an excellent sense of smell. They feed on fruits (especially figs), leaves, flowers, and nectar. The fruit bats are therefore particularly important for the distribution of the fruit seeds, especially over long distances between islands and for larger seeds such as those of the catappen tree . The Ryukyu fruit bats sleep in trees during the day, preferably in dense forests. There and in orchards and populated areas, they look for food at night. They can be seen hanging upside down in trees individually or in small groups. The generation length of the fruit bats is 6 to 8 years.
Wings of the Ryukyu flying fox
P. d. yayeyamae , male ventral
P. d. yayeyamae , male dorsal
Ryukyu fruit bats while eating
Distribution area and total population
 ![reference = [[Tokara Islands]]](https://de.wikipedia.org/wiki/Datei:Blue_pog.svg){kind=small}
![reference = [[Daitō Islands]]](https://de.wikipedia.org/wiki/Datei:Yellow_pog.svg){kind=small}
![reference = [[Okinawa Islands]]](https://de.wikipedia.org/wiki/Datei:Cyan_pog.svg){kind=small}
![reference = [[Miyako Islands]]](https://de.wikipedia.org/wiki/Datei:Green_pog.svg){kind=small}
![reference = [[Guishan Dao]]](https://de.wikipedia.org/wiki/Datei:Red_pog.svg){kind=small}
![reference = [[Philippines]]](https://de.wikipedia.org/wiki/Datei:Black_pog.svg){kind=small}
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Distribution areas and endangerment of the subspecies of the Ryukyu flying fox
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The Ryukyu flying fox is widespread on the eponymous Ryūkyū Islands of Japan as well as on some islands off the coast of Taiwan and in the north of the Philippines. Within the Japanese Ryūkyū Islands, the species is found on the Ōsumi Islands , Tokara Islands ( Nakano , Taira-jima , Akuseki-jima , Takara-jima ), Okinawa Islands , Yaeyama Islands ( Ishigaki-jima , Taketomi-jima , Kohama-jima , Iriomote-jima , Hateruma-jima , Kuroshima , Hatoma , Aragusuku-jima , and Yonaguni ), Miyako Islands ( Tarama-shima , Irabu-jima , Miyako-jima ) and Daitō Islands . In the Philippines, the fruit bats live on the northern islands of Batan , Babuyan Claro , Dalupiri and Fuga . In Taiwan there are only a few individuals on the islands of Lü Dao (Green Island) and Guishan Dao . The total range of the species has an area of over 650,000 km², of which, however, only about 300 to 600 km² are actually inhabited by the flying foxes, since the majority of the area consists of sea surface.
The total population of the species is estimated at 3000 to 6000 animals. A more precise estimate of the population size only exists for a few smaller islands. The largest populations live on the Okinawa Islands (subspecies P. d. Inopinatus ) and the Yaeyama Islands (subspecies P. d. Yayeyamae ). Their total population probably consists of a few thousand flying foxes each. In the northernmost distribution area, the subspecies P. d. Is found on only a few smaller islands . dasymallus . Their population is estimated at fewer than 200 individuals. A population census was carried out on the two Daitō Islands, which resulted in an estimate of 300 to 500 fruit bats. There are no estimates of the population in the Philippines, but some reports suggest a small population size. In Taiwan the subspecies P. d. formosus close to extinction. Two individuals were found on Lü Dao in 2005 - the first time since 1976 - and four more some time later. A small population of 20 animals was rediscovered on Guishan Dao in 2010.
Threats and vulnerability status
On the Japanese islands, the habitat of the fruit bats has declined due to the deforestation of forests for settlement construction and conversion to sugar cane, banana and pineapple plantations. Another threat is the killing of fruit bats by farmers who fear that their crops will be damaged. This is particularly devastating in connection with the occurrence of typhoons , which kill other fruit bats and their food sources. Animals killed by dogs, cats and power lines have also been detected.
In Taiwan, the hunting of fruit bats eradicated the subspecies P. d. formosus on the main Taiwanese island in the 1970s. On the island of Lü Dao there was originally a population of around 2000 animals, but animals were also hunted by humans here. In addition, invasive Pallas squirrels ( Callosciurus erythraeus ) represent a serious competitor for food. As a result, the population declined so much that the population was thought to have been extinct for 30 years before some individuals were finally rediscovered in 2005.
In the Philippines, fruit bats are hunted as a delicacy. Little is known about the local populations.
The IUCN classified Pteropus dasymallus into the category of threat endangers one ( "Vulnerable"). On the National Red List of Endangered Mammals of Japan , the two subspecies P. d. daitoensis (Japaneseダ イ ト ウ オ オ コ ウ モ リ, Daitō-Ōkōmori ) and P. d. dasymallus (Japaneseエ ラ ブ オ オ コ ウ モ リ, Erabu-Ōkōmori ) classified as critically endangered within Japan . Two species are also designated as national natural monuments . The Okinawa Prefecture arranges the subspecies P. d. inopinatus and P. d. yayeyamae as potentially endangered one ( "Near Threatened").
Systematics
The species Pteropus dasymallus was first described in 1825 by the Dutch zoologist Coenraad Jacob Temminck .
Four subspecies are recognized in Japan
- P. d. dasymallus ( Tokara Islands )
- P. d. daitoensis ( Daitō Islands )
- P. d. inopinatus ( Okinawa Islands )
- P. d. yayeyamae ( Yaeyama Islands ).
The subpopulation in Taiwan forms another subspecies
- P. d. formosus
literature
- Lee, YF, Takaso, T., Chiang, TY, Kuo, YM, Nakanishi, N., Tzeng, HY and Yasuda, K. 2009. Variation in the nocturnal foraging distribution of and resource use by endangered Ryukyu flying foxes (Pteropus dasymallus ) on Iriomotejima Island . Japan Contrib. Zool. 78: 51-64.
- Oliveros, C., Broad, G., Pedregosa, M., Espaňola, C., Reyes, M., Garcia, HJ, Gonzalez, JC, Bajarias, Jr., A. 2004. An avifaunal survey of the Babuyan Islands, Northern Philippines with notes on mammals, reptiles and amphibians , 29 March-6 June 2004. Unpublished report, Manilla.
- Trenberth, K. 2005. Uncertainty in hurricanes and global warming. Science 308: 1753-1754.
- Vincenot, CE, Collazo, AM, Wallmo, K. and Koyama, L. 2015a. Public awareness and perceptual factors in the conservation of elusive species: the case of the endangered Ryukyu flying fox . Global Ecol. Conservation 3: 526-540.
- Vincenot, CE, Koyama, L. and Russo, D. 2015b. Near threatened? First report of unsuspected human-driven decline factors in the Ryukyu flying fox (Pteropus dasymallus) in Japan . Mammalian Biology — Journal of Mammals 80: 273-277.
- Vincenot, CE, Collazo, AM and Russo, D. 2017. The Ryukyu flying fox (Pteropus dasymallus) - A review of conservation threats and call for reassessment . Mammalian Biology - Journal of Mammalian Science (in press). PDF
Web links
- Pteropus dasymallus in the endangered Red List species the IUCN 2017. Posted by: Vincenot, C., 2017. Accessed April 21 2021st
- Giant bat species reemerges after 30 years on edge. Taipei Times, Chao, VY, 2010, accessed April 21, 2021 .
Individual evidence
- ↑ a b c Giant bat species reemerges after 30 years on edge. Taipei Times, Chao, VY, 2010, accessed April 21, 2021 .
- ↑ a b c d e f Pteropus dasymallus in the endangered species Red List of IUCN 2017. Submitted By: Vincenot, C., 2017. Retrieved on 21 April 2021st
- ↑ Vincenot, CE, Koyama, L. and Russo, D. 2015b. Near threatened? First report of unsuspected human-driven decline factors in the Ryukyu flying fox (Pteropus dasymallus) in Japan . Mammalian Biology — Journal of Mammals 80: 273-277.
- ↑ a b Vincenot, CE, Collazo, AM and Russo, D. 2017. The Ryukyu flying fox (Pteropus dasymallus) - A review of conservation threats and call for reassessment . Mammalian Biology - Journal of Mammalian Science (in press). PDF
- ↑ Lee, YF, Takaso, T., Chiang, TY, Kuo, YM, Nakanishi, N., Tzeng, HY and Yasuda, K. 2009. Variation in the nocturnal foraging distribution of and resource use by endangered Ryukyu flying foxes (Pteropus dasymallus) on Iriomotejima Island . Japan Contrib. Zool. 78: 51-64.
- ↑ Oliveros, C., Broad, G., Pedregosa, M., Espaňola, C., Reyes, M., Garcia, HJ, Gonzalez, JC, Bajarias, Jr., A. 2004. An avifaunal survey of the Babuyan Islands , Northern Philippines with notes on mammals, reptiles and amphibians , 29 March-6 June 2004. Unpublished report, Manilla.
- ↑ Vincenot, C. 2017. Pteropus dasymallus. The IUCN Red List of Threatened Species 2017: e.T18722A22080614 . Downloaded on April 11, 2021.
- ↑ 環境 省 レ ッ ド リ ス ト 2020 (Red List 2020). (PDF, 662 KB) Japan Ministry of the Environment, accessed April 21, 2021 (Japanese).
- ↑ ダ イ ト ウ オ オ コ ウ モ リ ( P. d. Daitoensis ).国 指定 文化 財 等 デ ー タ ベ ー ス, accessed May 2, 2021 (Japanese).
- ↑ エ ラ ブ オ オ コ ウ モ リ ( P. d. Dasymallus ).国 指定 文化 財 等 デ ー タ ベ ー ス, accessed May 2, 2021 (Japanese).
- ^ Okinawa Prefecture. 2005. Revised Edition of the Okinawa Red Data Book (Japanese).